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This is purely for education and show. I worked on two top-50 supercomputer clusters for science applications. You learn a lot by doing. You find out what happ
by TwoNineFive 7y ago
This is purely for education and show.
I worked on two top-50 supercomputer clusters for science applications. You learn a lot by doing. You find out what happens to your electrical power, TFTP, DHCP, and syslog servers, and other infrastructure when those hundreds/thousands of nodes boot up all at once. Your Cisco switch reloads when you add a secondary IP address to all of your network interfaces because it's CAM table overflows. You learn how to automate without stuff like Ansible and Chef because they don't exist yet.
- intpx 7y agoHa, it was my experience with HPC that lead me to convince our CCIE network admin that CAM tables even could overload on a vlan of that size (we were using layer 3 switching to route tons of other vlans and this particular vlan was very active in traversing those boundaries and was also using multicast and lots of other weird things). We were seeing an issue when where computers on the same switch would lose their ability to see each other, even if they could see other machines on a different switch and everything about it smelled like the cam table was not accepting new entries. I finally convinced him to clear it out on one affected port and it worked.